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Modifiers are commonly used in natural, biological, and synthetic crystallization to tailor the growth of diverse materials. Here, we identify tautomers as a new class of modifiers where the dynamic interconversion between solute and its corresponding tautomer(s) produces native crystal growth inhibitors. The macroscopic and microscopic effects imposed by inhibitor-crystal interactions reveal dual mechanisms of inhibition where tautomer occlusion within crystals that leads to natural bending, tunes elastic modulus, and selectively alters the rate of crystal dissolution. Our study focuses on ammonium urate crystallization and shows that the keto-enol form of urate, which exists as a minor tautomer, is a potent inhibitor that nearly suppresses crystal growth at select solution alkalinity and supersaturation. The generalizability of this phenomenon is demonstrated for two additional tautomers with relevance to biological systems and pharmaceuticals. These findings offer potential routes in crystal engineering to strategically control the mechanical or physicochemical properties of tautomeric materials.

The main purpose of the current research is to pilot study the impact damage detection in a beam structure using infrared thermography. In this study, a beam structure, made of polyvinyl alcohol fiber reinforced engineering cementitious composite (PVA-ECC) was subjected to multiple low-velocity impacts at a constant energy level. After each impact, the structure was heated by means of halogen lamp, and acquisition of thermal images was conducted simultaneously. Sequences of thermal images were acquired with starting and ending time sets so as to include the entire evolution of thermal phenomenon, during both heating to cooling processes. Based on the relationship between the damage and the temperature variation under the thermal excitation, different damages in the impacted structures were analyzed in the thermographs. Through experimental investigation, the results demonstrated that different degrees of damage correspond to different infrared thermal characteristics. The generation and evolution of thermal signatures revealed the initiation and propagation of impact damages. It further illustrated that the proposed method is an innovative and effective approach to detect impact damage. [ABSTRACT FROM AUTHOR]

The article talks about dieletric materials such as insulators, resonators and capacitors that are vital components in electronic circuits that are used for energy storage applications. Topics discussed include future advancements in flexible technology requiring mechanically compliant dielectric materials.